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Cleaning of two mirrors in the first mirror unit using radiofrequency capacitively coupled plasma
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作者 Chenxue WANG Rong YAN +5 位作者 Yuming LIU Su XU Lei MU Wei ZHENG Rui DING Junling CHEN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第9期165-171,共7页
First mirror(FM)cleaning,using radio frequency(RF)plasma,has been proposed to recover FM reflectivity in nuclear fusion reactors such as the International Thermonuclear Experimental Reactor(ITER).To investigate the in... First mirror(FM)cleaning,using radio frequency(RF)plasma,has been proposed to recover FM reflectivity in nuclear fusion reactors such as the International Thermonuclear Experimental Reactor(ITER).To investigate the influence of simultaneous cleaning of two mirrors on mirror cleaning efficiency and uniformity,experiments involving single-mirror cleaning and dual-mirror cleaning were conducted using RF capacitively coupled plasma in the laboratory.For the test and simultaneous cleaning of two mirrors,the FM and second mirror(SM),both measuring 110 mm×80 mm,were placed inside the first mirror unit(FMU).They were composed of 16 mirror samples,each with a dimension of 27.5 mm×20 mm.These mirror samples consist of a titanium-zirconium-molybdenum alloy substrate,a 500 nm Mo intermediate layer and a 30 nm Al_(2)O_(3) surface coating as a proxy for Be impurities.The cleaning of a single first mirror(SFM)and the simultaneous cleaning of the FM and SM(DFM and DSM)lasted for 9 h using Ar plasma at a pressure of 1 Pa.The total reflectivity of mirror samples on the DSM did not fully recover and varied with location,with a self-bias of−140 V.With a self-bias of−300 V,the total reflectivity of mirror samples on the SFM and DFM was fully recovered.The energy dispersive spectrometer results demonstrated that the Al_(2)O_(3) coating had been completely removed from these mirror samples.However,the mass loss of each mirror sample on the SFM and DFM before and after cleaning varied depending on its location,with higher mass loss observed for mirror samples located in the corners and lower loss for those in the center.Compared with SM cleaning,the simultaneous cleaning of two mirrors reduced the difference between the highest and lowest mass loss.Furthermore,this mass loss for the mirror samples of the DFM facing the DSM was increased.This indicated that mirror samples cleaned face to face in the FMU simultaneously could influence each other,highlighting the need for special attention in future studies. 展开更多
关键词 first mirror unit dual-mirror cleaning REFLECTIVITY sputtering rate
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Reanalysis on the Spectral Characteristics and Materials of Jade Jue Unearthed from Lijiashan Ancient Tomb in Yunnan Province, China
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作者 Ting Fang Jifu Liu Mingxing Yang 《宝石和宝石学杂志(中英文)》 CAS 2024年第2期48-55,共8页
Jade ware Jue is one of the most fashionable ornament in ancient China from the Neolithic Age to the Han Dynasty.In this study,the remnants of jade ware Jue,from Lijiashan ancient tomb group have been tested and analy... Jade ware Jue is one of the most fashionable ornament in ancient China from the Neolithic Age to the Han Dynasty.In this study,the remnants of jade ware Jue,from Lijiashan ancient tomb group have been tested and analyzed respectively.The samples through a light etch surface showing glass luster and those with a severe etch surface showing earthen luster.With the aid of X-ray fluorescence Spectrometer(X-ray Fluorescence)test and X-ray diffraction(XRD)detection,the results show that tremolite is not the main mineral of the sample.The main components of the tested samples with light erosion are antigorite and talc,although the main components of the samples with severe erosion are calcite containing calcium carbonate barium.Furthermore,the research on jade ware Jue in Yunnan culture has not only contributed to our further understanding of the jade objects from Yunnan culture and the variety of jade material located in the Yunnan Province.It also provides a basis for the trace of the history and culture through the distribution and evolution of burial hierarchy laws.At the same time,the microscopic observation of the tested samples manifested a residual trace of“string”at the perforation,which has played a critical role in restoring the wearing of jade ware Jue from the tombs of the ancient Yunnan State and the handicraft skills at that time. 展开更多
关键词 Dian culture jade Jue corroded ancient jade XRD erosion mechanism Yunnan China
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From Mirror Theory to Oedipus Complex:A Lacanian Interpretation of Night,Mother
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作者 LIU Mu-zi 《Journal of Literature and Art Studies》 2024年第9期759-764,共6页
Jacques Lacan reinterpreted Freud’s psychoanalytic theory based on Saussure’s linguistics,and his theories such as the Mirror stage and the Oedipus complex had a significant impact on contemporary psychoanalysis.In ... Jacques Lacan reinterpreted Freud’s psychoanalytic theory based on Saussure’s linguistics,and his theories such as the Mirror stage and the Oedipus complex had a significant impact on contemporary psychoanalysis.In the play Night,Mother,the reasons for Jessie’s tragedy are diverse,among which the excessive protection of Jessie by her mother Thelma is an important reason for Jessie’s tragedy.Starting from Lacan’s Mirror stage theory and the Oedipus complex,this paper will explore how this intimate but heavy maternal love influenced Jessie’s path to finding her true“ego”. 展开更多
关键词 mirror stage Oedipus complex mother-daughter relationships identity construction
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Mirror Stage Theory Analysis of Bravery in Zootopia(2016)and Nezha(2019)
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作者 ZOU Jia-cheng 《Journal of Literature and Art Studies》 2024年第1期40-47,共8页
American Hollywood animated films have conquered the world.In recent years,many successful works have appeared in domestic animated films,bringing new vitality to the Chinese animated film industry.Based on Lacan’s M... American Hollywood animated films have conquered the world.In recent years,many successful works have appeared in domestic animated films,bringing new vitality to the Chinese animated film industry.Based on Lacan’s Mirror Stage Theory,this study attempts to start from the bravery of Judy and Nezha,the protagonists of Zootopia(2016)and Nezha(2019).It analyzes and compares their embodiment,formation,influence and reflection with real society to solve the problems of the two brave characters’formation causes,characteristic differences and social influences,including racial discrimination,individualism in American society and family problems in Chinese society.This study sheds light on the transmission of intercultural values in animated films. 展开更多
关键词 mirror Stage theory Zootopia Nezha:Birth of the Demon Child Judy Nezha Bravery
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The Application of Newmark’s Metaphor Theory in Novel Translation--A Case Study of“the Jade King:History of a Chinese Muslim Family”
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作者 Yuchen Xiao 《教育研究前沿(中英文版)》 2024年第3期100-112,共13页
This paper examines the metaphorical part of“The Jade King:History of a Chinese Muslim Family”,Hoda’s novel,under the guidance of Newmark’s theory of metaphor.Newmark proposes six categories of metaphors,namely De... This paper examines the metaphorical part of“The Jade King:History of a Chinese Muslim Family”,Hoda’s novel,under the guidance of Newmark’s theory of metaphor.Newmark proposes six categories of metaphors,namely Dead Metaphor,ClichéMetaphor,Stock or Standard Metaphor,Adapted Metaphor,Recent Metaphor,Original Metaphor;and seven strategies of metaphor translation,including reproducing the same image in the target language,replacing the image in the source language with a standard target language image,translation of metaphor by simile,translation of metaphor(or simile)by simile plus sense,conversion of metaphor to sense,deletion and same metaphor combined with sense.They can provide a strong theoretical support for analyzing the expressions of metaphors in novels and their translation methods.By deeply analyzing the expressions of metaphor and its translation methods in novels,it not only helps to understand the metaphorical meaning and cultural connotation of the original works,but also helps to explore the cultural differences and challenges faced by English and Chinese bilingualism in the process of metaphor translation,thereby significantly improving the translation level and promoting the development of translation research. 展开更多
关键词 METaPHOR Novel Translation the jade King:History of a Chinese Muslim Family”
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Improved mass relations of mirror nuclei
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作者 Cheng Xu Man Bao 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第9期178-185,共8页
In this study,we revisit the previous mass relations of mirror nuclei by considering 1/N-and 1/Z-dependent terms and the shell effect across a shell.The root-mean-squared deviation is 66 keV for 116 nuclei with neutro... In this study,we revisit the previous mass relations of mirror nuclei by considering 1/N-and 1/Z-dependent terms and the shell effect across a shell.The root-mean-squared deviation is 66 keV for 116 nuclei with neutron number N≥10,as com-pared with experimental data compiled in the AME2020 database.The predicted mass excesses of 173 proton-rich nuclei,including 98 unknown nuclei,are tabulated in the Supplemental Material herein with competitive accuracy. 展开更多
关键词 Nuclear mass mirror nuclei Proton-rich nuclei
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Fuzzy Proportional Integral Derivative control of a voice coil actuator system for adaptive deformable mirrors
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作者 Ziqiang Cui Heng Zuo +4 位作者 Weikang Qiao Hao Li Fujia Du Yifan Wang Jinrui Guo 《Astronomical Techniques and Instruments》 CSCD 2024年第3期179-186,共8页
Research on adaptive deformable mirror technology for voice coil actuators(VCAs)is an important trend in the development of large ground-based telescopes.A voice coil adaptive deformable mirror contains a large number... Research on adaptive deformable mirror technology for voice coil actuators(VCAs)is an important trend in the development of large ground-based telescopes.A voice coil adaptive deformable mirror contains a large number of actuators,and there are problems with structural coupling and large temperature increases in their internal coils.Additionally,parameters of the traditional proportional integral derivative(PID)control cannot be adjusted in real-time to adapt to system changes.These problems can be addressed by introducing fuzzy control methods.A table lookup method is adopted to replace real-time calculations of the regular fuzzy controller during the control process,and a prototype platform has been established to verify the effectiveness and robustness of this process.Experimental tests compare the control performance of traditional and fuzzy proportional integral derivative(Fuzzy-PID)controllers,showing that,in system step response tests,the fuzzy control system reduces rise time by 20.25%,decreases overshoot by 78.24%,and shortens settling time by 67.59%.In disturbance rejection experiments,fuzzy control achieves a 46.09%reduction in the maximum deviation,indicating stronger robustness.The Fuzzy-PID controller,based on table lookup,outperforms the standard controller significantly,showing excellent potential for enhancing the dynamic performance and disturbance rejection capability of the voice coil motor actuator system. 展开更多
关键词 adaptive optics Deformable mirror Voice coil actuator Fuzzy control
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Virtual Reality-Based Mirror Therapy for Upper Extremity Function among Stroke Patients:A Meta-analysis and Systematic Review
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作者 Juan ZHOU 《Medicinal Plant》 2024年第5期44-49,共6页
[Objectives]To investigate the evidence-based effect of virtual reality-based mirror therapy system(VR-MT)on upper extremity function among stroke patients.[Methods]A systematic electronic searching of the Medline,Pub... [Objectives]To investigate the evidence-based effect of virtual reality-based mirror therapy system(VR-MT)on upper extremity function among stroke patients.[Methods]A systematic electronic searching of the Medline,PubMed,Web of Science and CNKI was initially performed up to June 10,2024.The risk of bias of the included studies was evaluated using RevMan 5.4 software based on the Cochrane Handbook for Systematic Reviews.The random-effects model or fixed-effects models was employed to estimate the standardized mean difference(SMD).The subgroup analyses were conducted exploring theVR-MT type(immersive or non-immersive)and comparing with MT or control group.[Results]In total 8 studies with a total of 273 stroke patients were included in this review.The pooled analysis of these trials showed a statistically significant enhancement inFMA-UE scores(6 studies,SMD=0.72,[95%CI 0.37 to 1.06];P<0.0001,I^(2)=31%)and Box and Block Test(BBT)(3 studies,SMD=0.49,[95%C/0.05 to 0.93];P=0.03,I^(2)=0%),rather than Manual Function Test(MFT)scores(3 studies,SMD=0.38,[95%CI-0.09 to 0.84];P=0.11,I^(2)=0%)following the application of reality-based mirror therapy.Additionally,the subgroup analysis results indicated that immersive VR-MT can significantly improve FMA-UE(5studies,SMD=0.73,[95%CI 0.24 to 1.23];P=0.004,I^(2)=43%).In contrast,the overall effect of non-immersive VR-MT was non-significant(2 studies,SMD=0.33,[95%CI-0.69 to 1.34];P=0.53,I^(2)=72%).[Conclusions]In this systematic review and meta-analysis,our findings indicate that immersiveVR-MT has the potential to improve upper extremity function among stroke patients. 展开更多
关键词 STROKE mirror therapy Virtual reality Upper extremity function METa-aNaLYSIS
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The 108th plenary meeting of IEC/TC 61 held in Hangzhou
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《China Standardization》 2024年第4期14-14,共1页
Hosted by IEC,the 108th plenary meeting of IEC/TC 61 was held on June 3-7 in Hangzhou,Zhejiang province,which was supported by CHEARI Cixi Appliance Testing Service Co.,Ltd.,Zhejiang Tianxi Kitchen Appliance Co.,Ltd.,... Hosted by IEC,the 108th plenary meeting of IEC/TC 61 was held on June 3-7 in Hangzhou,Zhejiang province,which was supported by CHEARI Cixi Appliance Testing Service Co.,Ltd.,Zhejiang Tianxi Kitchen Appliance Co.,Ltd.,and Zhejiang Institute of Standardization.China Household Electric Appliance Research Institute(CHEARI)serves as the national mirror committee.With a focus on the framework restructuring of IEC/TC 61 and dozens of proposals related to the IEC 60335 series,the meeting was attended by Liu Ting,President of CHEARI,Qu Zongfeng,Vice President of CHEARI,Tang Jianhui,Deputy Director of Standardization Division of Zhejiang Administration for Market Regulation,Irma Rustemi,Chair of IEC/TC 61,Ma Dejun,Vice Chair of IEC/TC 61,Randi Myers,Secretary of IEC/TC 61,Christophe Boyer,Technical Officer of IEC,and over 200 experts at home and abroad. 展开更多
关键词 DIRECTOR Hangzhou mirror
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Constraining nuclear symmetry energy with the charge radii of mirror-pair nuclei 被引量:6
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作者 Rong An Shuai Sun +1 位作者 Li-Gang Cao Feng-Shou Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第8期154-163,共10页
The nuclear charge radius plays a vital role in determining the equation of state of isospin asymmetric nuclear matter.Based on the correlation between the differences in charge radii of mirror-partner nuclei and the ... The nuclear charge radius plays a vital role in determining the equation of state of isospin asymmetric nuclear matter.Based on the correlation between the differences in charge radii of mirror-partner nuclei and the slope parameter(L)of symmetry energy at the nuclear saturation density,an analysis of the calibrated slope parameter L was performed in finite nuclei.In this study,relativistic and nonrelativistic energy density functionals were employed to constrain the nuclear symmetry energy through the available databases of the mirror-pair nuclei^(36)Ca–^(36)S,^(38)Ca–^(38)Ar,and ^(54)Ni–^(54)Fe.The deduced nuclear symmetry energy was located in the range 29.89–31.85 MeV,and L of the symmetry energy essentially covered the range 22.50–51.55 MeV at the saturation density.Moreover,the extracted L_(s) at the sensitivity density p_(s)=0.10 fm^(-3) was located in the interval range 30.52–39.76 MeV. 展开更多
关键词 Symmetry energy Charge radii mirror nuclei
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Two types of mirror mode waves in the Kronian magnetosheath 被引量:1
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作者 XinYa Duanmu ZhongHua Yao +1 位作者 Yong Wei ShengYi Ye 《Earth and Planetary Physics》 EI CSCD 2023年第3期414-420,共7页
A mirror mode wave is a fundamental magnetic structure in the planetary space environment that is persistently compressed by solar wind,especially in the magnetosheath.Mirror modes have been widely identified in the m... A mirror mode wave is a fundamental magnetic structure in the planetary space environment that is persistently compressed by solar wind,especially in the magnetosheath.Mirror modes have been widely identified in the magnetosheaths of the Earth and other planets in the solar system,yet the understanding of mirror mode waves on extraterrestrial planets is not as comprehensive as that on the Earth.Using magnetic field data collected by the Cassini spacecraft,we found peak and dip types according to the magnetic morphology(i.e.,structures with higher or lower magnetic strengths than the background field).Moreover,mirror mode waves and electromagnetic ion cyclotron waves were found one after the other,implying that the two wave modes may evolve into one another in the Kronian magnetosheath.The results indicate that many fundamental plasma processes associated with the mirror mode structure exist in the Kronian magnetosheath.The energy conversion in Saturn’s magnetosheath may provide key insights that will aid in understanding giant planetary magnetospheric processes. 展开更多
关键词 mirror mode wave CaSSINI Kronian magnetosheath electromagnetic ion cyclotron wave
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STABILITY CONDITIONS AND THE MIRROR SYMMETRY OF K3 SURFACES IN ATTRACTOR BACKGROUNDS
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作者 卢文轩 《Acta Mathematica Scientia》 SCIE CSCD 2023年第3期1007-1030,共24页
We study the space of stability conditions on K3 surfaces from the perspective of mirror symmetry. This is done in the attractor backgrounds(moduli). We find certain highly non-generic behaviors of marginal stability ... We study the space of stability conditions on K3 surfaces from the perspective of mirror symmetry. This is done in the attractor backgrounds(moduli). We find certain highly non-generic behaviors of marginal stability walls(a key notion in the study of wall crossings)in the space of stability conditions. These correspond via mirror symmetry to some nongeneric behaviors of special Lagrangians in an attractor background. The main results can be understood as a mirror correspondence in a synthesis of the homological mirror conjecture and SYZ mirror conjecture. 展开更多
关键词 mirror symmetry stability conditions K3 surfaces attractor mechanism
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Jade Collection of Emperor Qianlong in the Qing Dynasty
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作者 MA Lin 《Journal of Literature and Art Studies》 2023年第2期129-134,共6页
During the reign of emperor Qianlong of the Qing Dynasty,the political rule was relatively stable,the economy continued to develop,and both civil and martial situations flourished.The emperor’s love for jade articles... During the reign of emperor Qianlong of the Qing Dynasty,the political rule was relatively stable,the economy continued to develop,and both civil and martial situations flourished.The emperor’s love for jade articles made this period a peak in the development of Chinese jade culture.Based on jade articles of emperor Qianlong collected in the Palace Museum and related documents and archives,this paper tries to explore characteristics of this collection and emperor Qianlong’s collecting methods,then explains that this collection not only has the functions of aesthetics,but also has the meaning of morality,religion and politics. 展开更多
关键词 Emperor Qianlong jade collection endow jade with virtue
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STRUCTURE OF BLACK PATINA ON THE ANCIENT BRONZE MIRRORS 被引量:1
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作者 马肇曾 杜凌 +2 位作者 方春英 尹秀兰 金莲姬 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1996年第2期126+121-126,共7页
X-ray diffaction analysis(XRDA)data of the black or brown patina on the surfaces of eight kinds of bronze mirror samples show 4 or 5 broad diffuse peaks which corresponding to almost the same 20 angle, while their mat... X-ray diffaction analysis(XRDA)data of the black or brown patina on the surfaces of eight kinds of bronze mirror samples show 4 or 5 broad diffuse peaks which corresponding to almost the same 20 angle, while their matixes does not.These results indicate that those diffuse peaks were produced by the SnO2, microcrystals of 3  ̄5 nm size contained in the black or brown patina.The matrix of unearthed black patina bronze mirror numbered 223, gives strong XRDA diffraction peaks, indicating that there are a large amounts of non-oxidized bronze alloy particles surrounded by SnO2,which shows that the black patinas are not wholly metallic oxides (mainly SnO2),there are also a lot of original alloys of different sizes in grain in the patina.The bright-field image of the black patina sample gives the same result. 展开更多
关键词 black patina on ancient bronze mirrors SnO2 microcrystal metallic corrosion
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Properties of focused Laguerre–Gaussian beam propagating in anisotropic ocean turbulence 被引量:1
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作者 王新光 马洋斌 +3 位作者 袁邱杰 陈伟 王乐 赵生妹 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期386-393,共8页
We analyze the properties of a focused Laguerre–Gaussian(LG)beam propagating through anisotropic ocean turbulence based on the Huygens–Fresnel principle.Under the Rytov approximation theory,we derive the analytical ... We analyze the properties of a focused Laguerre–Gaussian(LG)beam propagating through anisotropic ocean turbulence based on the Huygens–Fresnel principle.Under the Rytov approximation theory,we derive the analytical formula of the channel capacity of the focused LG beam in the anisotropic ocean turbulence,and analyze the relationship between the capacity and the light source parameters as well as the turbulent ocean parameters.It is found that the focusing mirror can greatly enhance the channel capacity of the system at the geometric focal plane in oceanic turbulence.The results also demonstrate that the communication link can obtain high channel capacity by adopting longer beam wavelength,greater initial beam waist radius,and larger number of transmission channels.Further,the capacity of the system increases with the decrease of the mean squared temperature dissipation rate,temperature-salinity contribution ratio and turbulence outer scale factor,and with the increase of the kinetic energy dissipation rate per unit mass of fluid,turbulence inner scale factor and anisotropy factor.Compared to a Hankel–Bessel beam with diffraction-free characteristics and unfocused LG beam,the focused LG beam shows superior anti-turbulence interference properties,which provide a theoretical reference for research and development of underwater optical communication links using focused LG beams. 展开更多
关键词 vortex beam orbital angular momentum focusing mirror anisotropic turbulence
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Intense Mid-Infrared Laser Pulse Generated via Flying-Mirror Red-Shifting in Near-Critical-Density Plasmas
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作者 鲁瑜 李东澳 +2 位作者 李倩妮 邵福球 余同普 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第2期42-46,共5页
Relativistic femtosecond mid-infrared pulses can be generated efficiently by laser interaction with near-criticaldensity plasmas.It is found theoretically and numerically that the radiation pressure of a circularly po... Relativistic femtosecond mid-infrared pulses can be generated efficiently by laser interaction with near-criticaldensity plasmas.It is found theoretically and numerically that the radiation pressure of a circularly polarized laser pulse first compresses the plasma electrons to form a dense flying mirror with a relativistic high speed.The pulse reflected by the mirror is red-shifted to the mid-infrared range.Full three-dimensional simulations demonstrate that the central wavelength of the mid-infrared pulse is tunable from 3µm to 14µm,and the laser energy conversion efficiency can reach as high as 13%.With a 0.5–10 PW incident laser pulse,the generated mid-infrared pulse reaches a peak power of 10–180 TW,which is interesting for various applications in ultrafast and high-field sciences. 展开更多
关键词 mirror Infrared Pulse
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First evidence for chiral wobbling of triaxial nuclei
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作者 S.Frauendorf 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第7期4-7,共4页
Chirality(Greek“handiness”)is a property of many com-plex molecules.Chiral molecules exist in two forms,one being the mirror image of the other.Like for our hands,it is impossible to make the images identical by a s... Chirality(Greek“handiness”)is a property of many com-plex molecules.Chiral molecules exist in two forms,one being the mirror image of the other.Like for our hands,it is impossible to make the images identical by a suitable rota-tion.The two forms are called left-handed and right-handed.They have the same binding energy,because the electro-magnetic interaction,which holds the molecule together,does not change under a reflection.Other properties that are insensitive to the geometry are also the same.The different geometry is the reason why the left-handed form turns the polarization plane of transmitted light in one direction by some angle while the right-handed form turns it in the oppo-site direction by the same angle.However,the geometrical differences between the two species may have other conse-quences.The two species of the carvon molecule shown in Fig.1 taste quite differently. 展开更多
关键词 TURNS CHIRaL mirror
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High-resolution visible imaging with piezoelectric deformable secondary mirror: experimental results at the 1.8-m adaptive telescope 被引量:2
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作者 Youming Guo Kele Chen +7 位作者 Jiahui Zhou Zhengdai Li Wenyu Han Xuejun Rao Hua Bao Jinsheng Yang Xinlong Fan Changhui Rao 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第12期15-26,共12页
Integrating deformable mirrors within the optical train of an adaptive telescope was one of the major innovations in astronomical observation technology,distinguished by its high optical throughput,reduced optical sur... Integrating deformable mirrors within the optical train of an adaptive telescope was one of the major innovations in astronomical observation technology,distinguished by its high optical throughput,reduced optical surfaces,and the incorporation of the deformable mirror.Typically,voice-coil actuators are used,which require additional position sensors,internal control electronics,and cooling systems,leading to a very complex structure.Piezoelectric deformable secondary mirror technologies were proposed to overcome these problems.Recently,a high-order piezoelectric deformable secondary mirror has been developed and installed on the 1.8-m telescope at Lijiang Observatory in China to make it an adaptive telescope.The system consists of a 241-actuator piezoelectric deformable secondary mirror,a 192-sub-aperture Shack-Hartmann wavefront sensor,and a multi-core-based real-time controller.The actuator spacing of the PDSM measures 19.3 mm,equivalent to approximately 12.6 cm when mapped onto the primary mirror,significantly less than the voicecoil-based adaptive telescopes such as LBT,Magellan and VLT.As a result,stellar images with Strehl ratios above 0.49 in the R band have been obtained.To our knowledge,these are the highest R band images captured by an adaptive telescope with deformable secondary mirrors.Here,we report the system description and on-sky performance of this adaptive telescope. 展开更多
关键词 adaptive optics deformable secondary mirror visible imaging
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An electromagnetic semi-active dynamic vibration absorber for thin-walled workpiece vibration suppression in mirror milling
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作者 Jianghua KONG Bei DING +3 位作者 Wei WANG Zhixia WANG Juliang XIAO Hongyun QIU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第8期1315-1334,共20页
As critical components of aircraft skins and rocket fuel storage tank shells,large thin-walled workpieces are susceptible to vibration and deformation during machining due to their weak local stiffness.To address thes... As critical components of aircraft skins and rocket fuel storage tank shells,large thin-walled workpieces are susceptible to vibration and deformation during machining due to their weak local stiffness.To address these challenges,we propose a novel tunable electromagnetic semi-active dynamic vibration absorber(ESADVA),which integrates with a magnetic suction follower to form a followed ESADVA(follow-ESADVA)for mirror milling.This system combines a tunable magnet oscillator with a follower,enabling real-time vibration absorption and condition feedback throughout the milling process.Additionally,the device supports self-sensing and frequency adjustment by providing feedback to a linear actuator,which alters the distance between magnets.This resolves the traditional issue of being unable to directly monitor vibration at the machining point due to space constraints and tool interference.The frequency shift characteristics and vibration absorption performance are comprehensively investigated.Theoretical and experimental results demonstrate that the prototyped follow-ESADVA achieves frequency synchronization with the milling tool,resulting in a vibration suppression rate of approximately 47.57%.Moreover,the roughness of the machined surface decreases by18.95%,significantly enhancing the surface quality.The results of this work pave the way for higher-quality machined surfaces and a more stable mirror milling process. 展开更多
关键词 semi-active dynamic vibration absorber(SaDVa) mirror milling selfsensing vibration absorption tuning thin-walled workpiece
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基于MaSE和JADE的交互式智能会议系统设计
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作者 罗轩 《自动化技术与应用》 2024年第11期200-204,共5页
针对当前系统通信架构较为落后,导致系统交互信息通信耗时较长且会议信息传输能耗较高的问题,提出基于MaSE和JADE的交互式智能会议系统。对系统硬件框架以及无线数据通信设备进行选型与优化。应用MaSE思想以及多Agent技术框架,设计多Ag... 针对当前系统通信架构较为落后,导致系统交互信息通信耗时较长且会议信息传输能耗较高的问题,提出基于MaSE和JADE的交互式智能会议系统。对系统硬件框架以及无线数据通信设备进行选型与优化。应用MaSE思想以及多Agent技术框架,设计多Agent通信模型。构建JADA系统框架,为多Agent通信模型提供运行环境。设定多Agent节点会议数据传输规则,优化会议信息交互传输路径。融合硬件与软件优化结果,完成交互式智能会议系统设计。实验结果表明:此系统可有效提升交互信息通信质量,并在一定程度上降低会议信息传输能耗,为交互式智能会议系统的研发提供新方向。 展开更多
关键词 jade平台 agent通信模型 数据传输 交互式智能会议系统
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